Marketing is hard work

Hello,
I am the owner of two businesses and they require all the time I have available. Marketing these businesses is just not easy. You can spend days promoting your products and services. This can go on totally alone, by itself, no other task involved. This fact is quite shocking to any neophyte businessman; he becomes bewildered by the amount of time he has to spend on marketing. I'm accustomed to the fact now, but in the beginning, it knocked me to the floor. You start out with hopes for a successful business, thinking it won't be too hard to succeed; then you are floored by what marketing that business will cost you in time and money. You then see why most businesses fail. The decision to stop or carry on appears abruptly - What should I do? I've made the choice to carry on, I know I will be very successful. But you like many others probably feel enough is enough and let it go. I guess that's the difference in me and others. We all are unique. Those are my thoughts for now, later.